To have clear vision the eye must be stabilized in space despite movements of the head and body. Several reflexes serve this function: the vestibulo-ocular reflex (VOR), in which semicircular canal stimulation causes compensatory eye movements, the optokinetic system, which moves the eyes to minimize retinal slip of the visual surroundings; and the visual and vestibular neck flexes, which stabilize the head. In birds the visual input for stabilization comes from an identifiable population of retinal ganglion cells to the nucleus of the basaloptic root (nBOR) of the accessory optic system and then goes directly to the oculomotor complex, as well as to the cerebellum and inferior olive. We propose to study these behaviors and the function of these pathways by several techniques. Single-unit recording from nBOR will reveal the optimal stimulus characteristics of both the inputs and outputs of this nucleus. Stimulation of nBOR and cutting its efferents may help clarify the nature of its direct oculomotor output. Studies on normal animals of VOR, optokinetic nystagmus, and visual and vestibular neck reflexes will permit comparison both with the electrophysiological findings and with the behavior shown by animals with lesions of nBOR, as well as giving a more complete picture of the several interacting systems that produce effective visual stabilization.